Steam-generator



No Model.)

T. L. & T. J. STURTEVANT.

STEAM GENERATOR.

IT /E 11 0 rs Patented June 27, 1893.

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UNITED STATES PATENT OFFICE.

THOMAS L. STURTEVANT AND THOMAS J. STURTEVA NT, OF FRAMINGIIAM, MASSACHUSETTS.

STEAM-GENERATOR.

SPECIFICATION forming part of Letters Patent No. 500,166, dated June 27, 1893.

Application filed August 1 To all whom it may concern.-

Be it known that we, THOMAS L. STURTE- VANT and THOMAS J. STURTEVANT, citizens of the United States, residing at Framingham, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Steam-Generators; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appe-rtains to make and use the same, reference being had to the accompanying drawings, and to figures of reference marked thereon, which form a part of this specification.

This invention relates to improvements in boilers and steam-generators, and consists in the general arrangement and co-operation of the several parts by which a more effective steam-generator and one especially adapted for liquid-fuel is produced.

The drawings represent in Figure 1 a front elevation of asteam-generator embodying our invention. Fig. 2 is a side elevation partly in section to show the generator for the saltwater system. Fig. 3 is a vertical section, as indicated by the plane y y in Fig. 2; while Fig. 4 represents the method of rendering the fresh and salt-water systems either conjoint or independent.

In the said drawings 2 represents a generator, composed of inner and outer shells respectively 3, 3 adapted to form an inverted n shaped steam and water chamber extending lengthwise of the generator .with an enlarged fire-box or combustion chamber 4. The lower portion of this is fitted with a grate 5, either composed of some refractory material or provided with grate-bars upon which rests material 6 of a refractory or analogous nature. Within and transversely of said firechamber are arranged cross-tubes 7 in banks or groups of staggered tubes, the banks alternating with each other in lieu of having single rows alternately disposed. We have found this to be an important matter, since it permits the rows of tubes to be staggered, but when cross-tubes'are arranged in rows alternately crossing the fire-chamber the upper tube openings are all so near together, that but little space is left for return to the Serial No. M1937. (No model.)

base, of water raised and discharged by the upper tube ends. The steam rising from the tube openings of the lower tubes strongly opposes the tendency of the water discharged by the upper tubes to return to the base. Hence two opposing currents are then set up, as soon as steam is generated in this type of boiler. Our invention remedies this difficulty.

I he tubes 7 in this generator are placed in alternate banks or groups of staggered inclined cross-tubes, see Fig. 2. The term staggered signifies that the tubes in. each group are notplaced in vertical planes successively one above another, but that each tube in a row of tubes is placed over the space between the tubes in the row below it. Consequently between each group of cross-tubes an open space 18 is left through which the water circulates freely, and through which some of the water, carried up by the tubes, falls freely to the base without being opposed by strong currents of steam arising from the openings of the tubes below. Thus in our generator there are no opposing currents of steam and water, and priming is infrequent.

In connection with this generator and its adaptability for liquid-fuel is the oil-injector 8 and the grate 5, in thepresent instance covered with some refractory material 6, together with a mechanically operated fan 9 located within a cap 10, which surmounts the stack.- In this way an induced draft is created when the fan is in rotation. Ordinarily the oil or liquid-fuel injected over the incandescent broken material placed on the grate-bars will burn with much smoke, owing to insufficient air-supply as in a common smoke-stack, and the tubes soon become covered with soot and the smoke openings closed; moreover a forced draft injected either above or below the grate localizes the heat too much, and the flame acts after the manner of a blow-pipe, and often destroys the tubes. Further the draft through the grate is unevenly distributed and poor combustion follows. In the use of liquid fuel, should there be any leak in the boilercasing the discharge of dangerous flame and gases is certain; while the act of opening a boiler door is in a high degree dangerous, if aforced draft is employed. Induced draft obviates all these difficulties, the oil burning freely with little or no smoke, when sprinkled over the material on the grate; this material 6, when once heated to incandescence remains long in a condition to ignite the oil-spray, and does not permit the flame to go out, while its radiant heat greatly promotes the making of k steam.

The products of combustion rise through the tube spaces directly to the stack 12,which extends above the top of the boiler and through the steam space formed by the dome 13 superheating the steam therein, and adding much to the efficiency of the structure while increasing its strength. It will be seen by reference to Fig. 3, that the dome is less in diameter than the top dimensions of the generator, and lateral offsets 19 are created; hence any water carried into the crown space is directed horizontally thereacross and is prevented from rising and intermingling with the steam in the dome, thereby retaining such steam in a drier condition. r

One of the most important features of this invention consists in the partially separate receiver 14 for salt-water; such receiver forming a part of the fire-chamber. This is a simple and easily cleansed structure in which salt-water can be evaporated and its steam outlet as shown in Fig. 4 be connected with the steam space of the generator and controlled bya valve 15. An independent steam discharge 16 and steam gage 17 is provided, if it should become necessary to use it separately. When the valve 15 is open a continuous addition of steam evaporated from the salt-water is made and added to the general stock carried in the generator.

legs, whereby said separate generator may be employed for evaporating salt water and the steam thus generated be conveyed into the steam space of the main generator, substantially as described.

2. The combination with a main steam generator or boiler, of an auxiliar generator, for

salt water use, said auxiliary generator being separate from the said main generator and being arranged to form a side wall of the fire chamber, and connections by which the steam from said auxiliary generator may be subsequently united with that from the main or fresh water generator.

3. The combination with a main generator or boiler, of an auxiliary generator, as 14, separate" from the main generator and arranged to form a side wall of the fire chamber, said auxiliary generator being furnished with an independent water supply and steam discharge pipes and steam gage.

In testimony whereof we afifix our signatures in presence of two witnesses.

THOMAS L.'STURTEVANT. THOMAS J. STURTEVANT.

Witnesses:

II. E. LODGE,

FRANCIS O. STANWOOD. 

